In the early 21st century, zombies were often associated with movies. To Ianto Jones, the typical horror movie zombie wore ragged, stained clothes, had discoloured skin and appeared in various stages of decomposition. In the movies, in order to kill a zombie, it had to be shot in the head, destroying the brain. According to Rhys Williams, zombie outbreaks were always caused by "chemicals or radiation or something". (PROSE: Bay of the Dead)

While not truly being "undead," it was possible (and often done by tribes in Haiti) to trick a human into believing they were one of the "living dead" using the drug tetrodotoxin. In correct doses, it could lower the consciousness of a person and take away their sensory nerves. The person would then be buried and dug up, making them think they had been brought back to life. They would subsequently be used as slaves. (PROSE: White Darkness)

In 1939, the Seventh Doctor called the SS soldiers who had been conditioned by the War Lords, zombies. These troops were able to avoid death owing to a literal realisation of the Prussianmilitary phrase, "corpse discipline": discipline that could make a corpse jump to attention. (PROSE: Timewyrm: Exodus) He later encountered much more conventional zombies on Arviem 2 with Bernice Summerfield; the result of a latent magnetronic field placed upon a swamp to convert and reanimate any dead organic matter, these zombies retained higher brain functions, and sometimes did not realise what they had become. They nonetheless harbored a desire to eat people's brains, preferably highly developed ones. As they were essentially walking corpses, the zombies kept decaying, and occasionally lost body parts; they did not appear able to feel this when it happened, and would remark curiously on how odd it was that they suddenly found organs on the ground around them. (AUDIO: The Revolution)

David A. McIntee, when writing White Darkness, took inspiration and facts from the non-fiction book The Serpent and the Rainbow, which detailed accounts of zombification that occurred in Haiti in the early 20th century. He advised staying away from the film version.